Electric heating apparatus.



W. S, HADAWAY, In.

ELECTRIC HEATING APPARATUS.

APPLICATION FILED SEPT.26.19131 1,167,749. Patented Jan. 11, 1916.

3 SHEETSSHEET I.

WI M58858 l/V I/E/V 70/? W77 2 y i; o 1 9. A/ 1 1, Y ATTORNEY COLUMBIAPLANOGRAFH' (10., WASHINGTON, n. C

W. S. HADAWAY, JR.

ELECTRIC HEATING APPARATUS.

3 SHEETS-SHEET 2.

WITNESSES 7? A TTORNEY COLUMBIA PLANOGRAPH C0,. WASHINGTON, D. c.

UNITED STATES PATENT OFFICE.

WILLIAM S. HADAWAY, JR., OF NEW ROCHELLE, NEW YORK.

ELECTRIC HEATING APPARATUS.

Application filed September 26, 1913.

To all whom it may concern Be it known that 1, WILLIAM S. HADA- WAY, Jr., a citizen of the United States, and a resident of New Rochelle,WVestchester county, and State of New York, have invented certain newand useful Improvements in Electric Heating Apparatus, of which thefollowing is a specification, reference being had to the accompanyingdrawings, forming a part thereof.

My invention relates to electric heating devices and particularly tosuch as are intended to impart heat to relatively distant objects.

One object of my invention is to provide a simple and durable heaterthat shall be arranged and constructed to transfer a large proportion ofits heat by radiation.

Another object is to provide a heater unit of the character aboveindicated that shall be inexpensive to construct and adapted to beutilized in groups or quantities depending upon the shape and size ofthe heating device of which it forms a part.

Other objects and advantages of my invention will be set forthhereinafter.

Figure 1 is a partially sectional elevation of a heater unit arrangedand constructed in accordance with my invention. Figs. 2 and l 3 aretransverse sectional views on the lines 22 and 33 of Fig. 1. Amodification of the unit of the preceding figures, with an inclosingcasing, is shown in Fig. 4. The utility of the open unit of Fig. 1 isillustrated in Fig. 5 which is a front elevation of a portable airheater. Fig. 6 is a sectional plan view of the same heater. Fig. 7 is afront elevation and Fig. 8 an end elevation of a toaster stove equippedwith and illustrating the utility of the inclosed heater unit of Fig. 4.

. Corresponding parts are designated by the same reference characters inall of the figures.

Referring to Figs. 1, 2 and 3 of the drawings, the heater unit hereshown comprises an attachment plug or thimble 10, a longitudinal rod 20,terminal members and 30, and a relatively high resistance heating.element 40. The plug or thimble 10 is preferably formed of sheet metalsuch as brass, and has helically corrugated side walls 11 which areformed to provide screw threads in a well known manner. The thimble isprovided with an aperture 12 at one end and a flange 13 at the oppositeend. The flange Specification of Letters Patent.

Patented Jan. 11, 1916.

Serial No. 791,931.

is bent back on itself to provide an annular groove 1% in which the body26 of the terminal member 25 is supported. Insulating washers 16 and 17are rigidly secured to the partially closed end of the thimble by meansof a hollow rivet 18 which is headed over metal washers 19. One end ofthe rod 20, which is screw-threaded near each end, extends through thehollow rivet 18 in the base of the plug or thimble and is clamped inposition by nuts 21 and 22. The body of the rod is separatedelectrically from the resistance wire d0 by means of an insulatingsleeve 23 which extends from the nut 22 near one end to a nut 31 whichforms a part of the terminal at the other end. The nut 31 and a similarbinding nut 32 are screwed onto the outer end of the rod 20 and clampbetween them the outer end of the resistance wire 40. The resistancewire may be coiled about the insulating sleeve 23 in any suitable mannerbut I prefer to arrange it in the form of a triangular helix as clearlyshown in Figs. 1 and 2 of the drawings, in order that the central rodmay support itagainst vibration. The opposite end of the wire is securedto the terminal which comprises the ring-shaped body 26, a tongue 27extending upwardly therefrom and a binding screw 28 in the tongue. Theinside diameter of the ring 26 is sufficiently large to permit the rod20 and the insulating sleeve 23 to extend freely through it and theaperture 12 in the partially closed end of the thimble or plug is ofsuch dimensions that the hollow rivet 18 and the thimble areelectrically separated. The nut 21 and the corresponding end of the rod20 are finished to a plane outer surface which is adapted to makecontact with the central contact of an attachment socket (not shown)into which the plug 10 is adapted to be screwed. The electric circuit isestablished, when the plug is inserted in an energized socket, from thenut 21 through the rod 20 to the terminal 30, through the resistancewire to the terminal 25 and thence to the body of the plug or thimblewhich is in engagement with the base ring of the terminal 25.

The inclosed heater of Fig. at is similar to the unit of the precedingfigures, which has just been described except that the plug is providedwith a casing socket into which a hollow prismatic casing is set. Thecasing comprises a frame 56 having hexagonal end pieces 56* and angleribs 56 connecting the end pieces. Transparent, heat resisting panels56preferably formed of mica, are set into the frame between the Conductionis the transfer of heat from one part of a body to another. Convectionis the transfer of heat by the motion ofheated matter and takes placeonly in fluids and gases. Radiation is the communication of heat from ahot body to a colder one across an intervening space and does not dependupon intervening air or any other tangible matter. The transfer of heatby radiation is supposed to be effected through the ether. Heat istransferred from electric heating devices, as ordinarily constructed,partly byv radiation and in some cases by conduction, but ordinarily itis largely transferred by convection. In many ways this is the mostunsatisfactory and uneconomical method of transferring heat and it hasbeen my aim to produce a heater which is so designed and operated that ayery large percentage of its heat is transferred, directly where it iswanted and used, by radiation. The intensity of heat radiation from agiven source, varies as the temperature of the source, and inversely asthe square of the distance from the source. .Consequently I havedesigned my heater units to operate at a very high temperature.Nevertheless each unit is particularly simple in construction, requiresno vacuum chamber or bulb and may be readily removed and replaced'ifdestroyed or injured. The heater units may be utilized singly or ingroups and it is not necessary to associate them with any particularreflecting or inclosing structure, but the units are well adapted forapplication to various devices and utensils for household and otherpurposes.

Referring to Figs. 5 and 6, the heater unit of Figs. 1, 2 and 3 is hereshown as applied to an air heater for general heating purposes. Thisheater comprises a casing 60 having a hollow rectangular terminal box 61which is secured at its ends to a' pair of end frames 62 and 63 and asheet metal back having a reflector surface 64 and an over hanging hood65 at the top. The end frames have foot projections 66 at the bottomwhich are adapted to rest on the floor or some suitable horizontalsupporting surface 67. They support the hollow terminal box 61materially above the floor level. The top of the terminal box isperforated to receive a plurality of sockets35 which are arranged withtheir adjacent sides substantially parallel in order that they may beset more closely to-' suitable surface such as polished silver, or

brass. The surface 64; is a surface of this character and is intendedand adapted to reflect the radiated rays so that all of the heat isradiated from the front of the heater. v

The toaster stove shown in Figs. 7 and 8 clearly indicates theadaptability of the inclosed heater units of Fig. at. This stovecomprises a pair of terminal boxes 70 and 71 which are supported by footprojections '72 and constitute the body of the, device, a rack 73slidably mounted between the terminal boxes and a plurality of inclosedheater units 75. These units are arranged in two groups of three each,although the number employed will depend entirely upon the size of thestove and the work to be performed. The top of each terminal box isperforated to receive sockets 35 in which the inclosed heater units aremounted. The rack may be formed in any suitable manner and preferablycomprises a pair of spaced screens 7 6 which are arranged to support aslice of bread between them.

The heater units may of course be applied to a large number of differentdevices within the spirit and scope of my invention, and I desire thatonly such limitations be imposed as are indicated in the appendedclaims.

lVhat I claim is: I

1. An electric heater comprising an attachment member having contactsadapted to engage cooperating receptacle contacts, a rigid conductorconnected to one of said contacts adapted to be supported solely by theattachment member and extending outwardly therefrom, and a heaterelement supported by the conductor and electrically connected at itsrespective ends to the outer end of the conductor and to another of saidattachment contacts. 7

2. A heater comprising a plug having a helically corrugated body adaptedto engage and make electrical contact with the interior walls of asocket and an end contact electrically separated from the body of theplug and adapted to make contact with the interior bottom contact of asocket, a con ducting rod secured to said end contact, an insulatingsleeve surrounding the rod, a terminal member secured to the body of theplug, an opposite terminal member at the outer end of the rod and aheater element connected at its respective ends to the terminal members.

3. An electric heater comprising an attachment plug, a casing socketsecured thereto and insulated therefrom, a conducting rod extendingoutwardly from the plug, a heater element arranged above the rod as asupport, a casing frame supported in said casing socket, translucentpanels supported by said frame, a cap at the outer end of said casingand an insulating nut screwed onto the end of the conducting rod forholding the parts of the casing together in position.

4. An electric heater comprising an attachment member, a casing socketsecured thereto and insulated therefrom, a central rod, a'heaterelement, a casing frame supported in the casing socket, a cap at theouter end of the casing and an insulating nut screwed onto the outer endof the central rod.

5. An electric heater comprising an attachment plug, a polygonal casingsocket secured thereto and insulated therefrom, a central rod extendingoutwardly from the plug, a heater element supported by the rod, a casingframe in the form of a hollow polygonal prism with open panels, set intothe casing socket, a cap fitted onto the outer end of the casing frame,and an insulating means afiixed to the outer end of the rod for bold ingthe parts of the casing together in position.

6. An electric heater comprising an attachment member, a casing socketsecured thereto, a central rod, a heater element, a casing frame havingpanels through which heat may be radiated and supported in the casingsocket, a cap at the outer end of the casing frame and means cooperatingwith the rod for removably holding the casing in position.

In witness whereof, I have hereunto set my hand this 24th day ofSeptember in the year 1913.

WILLIAM S. HADAlVAY, J n.

Vitnesses G. R. QUIMBY, F. B. GRAVES.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

